Adjustable optical fiber connector

ABSTRACT

A connector for an optical fiber includes a housing defining a lumen and having a proximal end and distal end, and an adjustable ferrule secured to the proximal end of the housing and rotatable with respect to the housing to translate a proximal end of the optical fiber longitudinally with respect to a proximal end of the adjustable ferrule.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to application Ser. No. 12/917,882,filed Nov. 2, 2010, which claims the benefit of Provisional ApplicationNo. 61/257,893, filed Nov. 4, 2009, each of which is incorporated hereinby reference in its entirety.

TECHNICAL FIELD

The present invention relates to optical fiber connectors. Morespecifically, the present invention relates to a reusable optical fiberconnector including an adjustable ferrule.

BACKGROUND

An optical fiber connector, which terminates the end of an opticalfiber, facilitates connection and disconnection of the optical fiber toother coupling elements. For example, when connecting two optical fibersto each other, the connector mechanically couples and aligns the coresof fibers so that light can pass. As another example, when the connectoris employed to mechanically and optically couple the optical fiber to anoptical system, such as industrial, medical, surgical, laser, andtelecommunications systems, the connector mechanically and opticallyconnects the optical fiber to allow delivery of optical signals to thesystem. The optical fiber connector couples the fiber core adjacent tothe receiving element to minimize the air space between the fiber coreand the coupling element, thereby preventing signal loss.

SUMMARY

In one aspect, the present disclosure relates to a connector for anoptical fiber. The connector includes a housing defining a lumen andhaving a proximal end and distal end. The connector also includes acollet configured to receive a portion of the optical fiber. The colletis disposed in the lumen such that the collet holds the optical fiber inplace with respect to the housing. An adjustable ferrule is secured tothe proximal end of the housing and is rotatable with respect to thehousing to translate a proximal end of the optical fiber longitudinallywith respect to a proximal end of the adjustable ferrule. A connectorelement is secured to the proximal end of the housing with theadjustable ferrule, and is rotatable with respect to the housing. Acollar is disposed around the housing and is secured to the connectorelement and spaced from the housing such that rotation of the collarrotates the connector element with respect to the housing.

In another aspect, the present disclosure relates to a connector for anoptical fiber including a housing defining a lumen and a proximal endand distal end. An adjustable ferrule is secured to the proximal end ofthe housing and is rotatable with respect to the housing to translate aproximal end of the optical fiber longitudinally with respect to aproximal end of the adjustable ferrule.

In a further aspect, the present disclosure relates to an optical fiberassembly including an optical fiber, a housing defining a lumen andincluding a proximal end and distal end, and an adjustable ferrulesecured to the proximal end of the housing and rotatable with respect tothe housing to translate a proximal end of the optical fiberlongitudinally with respect to a proximal end of the adjustable ferrule.

While multiple embodiments are disclosed, still other embodiments of thepresent invention will become apparent to those skilled in the art fromthe following detailed description, which shows and describesillustrative embodiments of the invention. Accordingly, the drawings anddetailed description are to be regarded as illustrative in nature andnot restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of an optical fiberconnector including an adjustable ferrule.

FIG. 2 is a cross-sectional view of the optical fiber connector shown inFIG. 1.

FIG. 3 is an exploded perspective view of the optical fiber connectorshown in FIG. 1.

FIG. 4A is a cross-sectional view of the optical fiber connector shownin FIG. 1, showing a proximal end of a fiber optic cable disposedsubstantially flush with a proximal end of the ferrule.

FIG. 4B is a cross-sectional view of the optical fiber connector shownin FIG. 1, showing the proximal end of the fiber optic cable recessedfrom the proximal end of the ferrule after adjustment.

FIG. 5A is a partial cross-sectional view of a protective shell suitablefor securing around the optical fiber connector.

FIG. 5B is an exploded view of the protective shell shown in FIG. 5A.

While the invention is amenable to various modifications and alternativeforms, specific embodiments have been shown by way of example in thedrawings and are described in detail below. The intention, however, isnot to limit the invention to the particular embodiments described. Onthe contrary, the invention is intended to cover all modifications,equivalents, and alternatives falling within the scope of the inventionas defined by the appended claims.

DETAILED DESCRIPTION

FIG. 1 is a perspective view, FIG. 2 is a cross-sectional view, and FIG.3 is an exploded perspective view of an embodiment of an optical fiberconnector 10 having a proximal end P and a distal end D. The opticalfiber connector 10 includes a housing 12 including a first couplingelement 14 and a second coupling element 16, a collet 18, a connectorelement 20, a ferrule 22, a collar 23, and a cap 24. In the embodimentshown, the optical fiber connector 10 also includes a strain reliefsleeve 26 coupled to a distal end of the first coupling element 14. InFIG. 1, the optical fiber connector 10 is coupled to an optical fiber28.

The first coupling element 14 includes a threaded bore 30 on itsproximal end that is configured to engage a screw member 32 on a distalend of the second coupling element 16. While a screw member 32 is shown,the coupling elements 14, 16 may alternatively include otherconfigurations to mechanically engage with each other. When engaged, thecoupling elements 14, 16 define a lumen 34 that is sized and shaped toretain the collet 18. In some embodiments, the lumen 34 includes ends 36having a first diameter D₁, a middle section 38 having a second diameterD₂ larger than the first diameter D₁, and frustoconical portions 40,which extend between the middle section 38 and ends 36 and transitionbetween the first diameter D₁ and the second diameter D₂. In someembodiments, the first coupling element 14 and the second couplingelement 16 are comprised of metal.

In some embodiments, the optical fiber connector 10 may include a collar23 that covers one or both of the coupling elements 14, 16. The collar23 is illustrate in phantom in FIG. 1. In embodiments in which thecollar covers both coupling elements 14, 16, the collar 23 preventsmanual or inadvertent decoupling of the coupling elements 14, 16 duringuse. The collar 23 may be secured to the connector element 20 with a setscrew 42. In some embodiments, the collar 23 is disposed a distance fromthe coupling elements 14, 16 (e.g., 50 μm), such that rotation of thecollar rotates the connector element 20 without rotating the underlyingcoupling elements 14, 16 with respect to each other. The collar 23 maybe color-coded to allow a user to discern between different versions ofthe optical fiber connector 10 that, for example, accommodate differentsized optical fibers 28. The collar 23 may also include labeling orother indicia to identify the manufacturer, the model number, the serialnumber, and so on. The labeling or indicia may be provided on the collar23 by, for example, laser marking.

The optical fiber connector 10 may also include one or more set screwsto secure or lock elements with respect to each other. For example, inthe embodiment shown in FIGS. 1-3, a set screw 44 is provided near thedistal end of the first coupling portion 14, and a set screw 46 isprovided near the proximal end of the second coupling portion 16. Theset screw 44 is received in a radially directed threaded bore 48extending through the first coupling element 14. The set screw 44 isactuatable to engage with the second coupling element 16 to lock thesecond coupling element 16 longitudinally with respect to the firstcoupling element 14. The set screw 46 is received in a radially directedthreaded bore 50 extending through the second coupling element 16. Theset screw 46 is actuatable to engage with the adjustable ferrule 22 tolock the adjustable ferrule 22 longitudinally with respect to the secondcoupling element 16. While the optical fiber connector 10 is shownincluding two set screws 44, 46 in FIGS. 1-3, it will be appreciatedthat the optical fiber connector 10 can include more or fewer set screwsto secure the components of the optical fiber 10 with respect to eachother.

The collet 18 is disposed in the lumen 34 and is configured to receivethe optical fiber 28. As the optical fiber 28 is fed through the opticalfiber connector 10 from the distal end D, the optical fiber 28 extendsthrough the strain relief sleeve 26, a central lumen L of the collet 18,and the adjustable ferrule 22. The collet 18 may be made of a polymericmaterial, such as polyaryletheretherketone (PEEK), polyethylene (PE),polytetrafluoroethylene (PTFE), high-density polyethylene (HDPE),fluorinated ethylene propylene (FEP), or other suitable medical gradepolymers. The collet 18 includes tapered ends 52 that are urged againstthe frustoconical portions 40 of the lumen 34 when the first and secondcoupling elements 14, 16 are secured together. This causes the taperedends 52 of the collet 18 to clamp against the optical fiber 28 to holdthe optical fiber 28 in place with respect to the collet 18. Theengagement of the frustoconical portions 40 with the tapered ends 52holds the collet 18 in place with respect to the coupling elements 14,16.

The connector element 20 is secured to the proximal end of the secondcoupling element 16 with the adjustable ferrule 22. That is, theadjustable ferrule 22 includes a threaded portion 54 that engages athreaded bore 56 at the proximal end of the second coupling element 16.A neck 58 on the proximal end of the threaded portion 54 holds theconnector element 20 in place with respect to the second couplingelement 16. When secured to the second coupling element 16, theconnector element 20 may be configured to rotate with respect to thesecond coupling element 16. This allows the optical fiber connector 10to be quickly and easily engaged to or disengaged from another connectoror an optical system. Example optical systems to which the optical fiberconnector 10 may be connected include, but are not limited to,industrial, medical, surgical, laser, and telecommunications systems.

In the embodiment shown, the connector element 20 is a threaded nut. Insome embodiments, the connector element 20 and adjustable ferrule 22 areconfigured and dimensioned as an SMA 905 connector. In otherembodiments, the connector element 20 and adjustable ferrule 22 areconfigured and dimensioned as other types of screw interface connectorsincluding, but not limited to, SMA 906, FSMA, FC, ADT-UNI, and Avio. Inalternative embodiments, the connector element 20 and adjustable ferrule22 may be configured to snap the optical fiber connector 10 to anotherconnector or an optical system, may be configured for push-pullengagement, or may be configured for other types of mechanicalengagement. For example, in some embodiments, the connector element 20and adjustable ferrule 22 are configured and dimensioned as connectortypes including, but not limited to, E-2000, EC, ESCON, F-3000,Fibergate, LC, LuxCis, MIC, MPO, MT, MT-RJ, MU, Opti-Jack, standardconnector (SC), VF-45, or V-PIN.

The adjustable ferrule 22 includes the distal threaded portion 54 thatis coupled to a proximal ferrule portion 60. In some embodiments, theferrule portion 60 is comprised of a ceramic material, such as zirconia.In other embodiments, the ferrule portion 60 is comprised of a metal,such as stainless steel. The adjustable ferrule 22 includes a centrallumen including a first portion 62 and a second portion 64. The firstportion 62 has a larger diameter than the second portion 64. The firstportion 62 is sized to receive the optical fiber 28 with the bufferlayer, and the second portion 64 is sized to receive the optical fiber28 with the buffer layer removed or stripped away along at least aportion of the optical fiber 28 in the second portion 64. In oneexemplary implementation, about ⅛ of the optical fiber 28 in the secondportion 64 is unbuffered. The second portion 64 may alternatively besized to also receive the optical fiber with the buffer layer intact.

The adjustable ferrule 22 may additionally include an arrangement in thefirst portion 62 and/or second portion 64 of the central lumen thatminimizes or prevents fluid or debris from entering the housing 12. Forexample, a sealing layer may be formed along at least a portion of thecentral lumen that supports the proximal end of the optical fiber 28 andprevents fluid and debris from infiltrating the housing through theproximal end P. The sealing layer may be arranged in the adjustableferrule 22 to allow the sealing layer to be compressed to create agasket or seal effect. In one exemplary implementation, the sealinglayer is provided in a cylindrical recess formed in the central lumen.In some embodiments, the sealing layer is comprised of a flexible andpliable material, such as silicone. In alternative embodiments, thesealing layer is comprised of other materials, such as epoxy or wax. Thesealing layer material may also be selected to allow the adjustableferrule to be subjected to high temperatures.

One advantage of the optical fiber connector 10 is that the componentsof the optical fiber connector 10 are assembled without the use of epoxyor crimping, resulting in a non-permanent assembly. In addition, theadjustability of the adjustable ferrule 22 allows the distance betweenthe optical fiber 28 to be set by the assembler of the optical fiberconnector 10, as will be discussed in more detail in FIGS. 4A and 4Bbelow.

Another advantage of the optical fiber connector 10 is the ability toreprocess the various components of the optical fiber connector 10 aftereach use. Due to this reusability, the life of the optical fiber 28 isincreased. In some embodiments, the optical fiber connector 10 and/oroptical fiber 28 are reprocessed in an assembled state using appropriatedecontamination techniques. For example, in one exemplarydecontamination process, the optical fiber 28 is decontaminated, theoptical fiber 28 at the proximal end P is inspected, and the opticalfiber 28 is again decontaminated before subjecting the optical fiberconnecter 10 and optical fiber 28 to a sterilization process (e.g.,steam sterilization). In some embodiments, the mechanical coupling ofthe optical fiber 28 to the connector 10 allows the optical fiber 28 tobe decoupled from the connector 10 and refurbished for reuse. That is,the optical fiber 28 may be removed from the connector 10, the proximalend of the optical fiber 28 cut and stripped, and the proximal end ofthe optical fiber 28 subsequently re-inserted into the connector 10 forpolishing or cleaving. In addition, the collet 18 can be easily removedfor refurbishing or replacement after a use by opening the housing 12.The remaining portions of the optical fiber connector 10, such as thehousing 12, the connector 20, and the adjustable ferrule 22 (includingthe sealing layer), are comprised of materials that can be subjected toautoclaving, radiation, chemical treatment (e.g., ethylene oxide), orother suitable reprocessing techniques.

FIGS. 4A and 4B illustrate the adjustability of the optical fiber 28with respect to the proximal end of the adjustable ferrule 22. In FIG.4A, the optical fiber 28 passes through the collet 18 in the housing 12and into the adjustable ferrule 22. The portion of the optical fiber 28in the first portion 62 of the adjustable ferrule 22 includes one ormore buffer layer(s) 68 around the fiber core 70, and at least a portionof the optical fiber 28 in the second portion 64 of the adjustableferrule 22 has the buffer layer(s) 68 stripped away, such that only thefiber core 70 is in the second portion 64. The optical fiber 28 isarranged such that the end face 72 of the fiber core 70 is substantiallyflush with the proximal end of the adjustable ferrule 22. The opticalfiber 28 may then be held in place by tightening the coupling elements14, 16 and engaging the set screw 44 with the second coupling element16. The set screw 46 may also be engaged with the adjustable ferrule 22to maintain the position of the adjustable ferrule 22. The end face 72may then be polished or cleaved and examined to minimize insertion lossof the optical fiber 28 and reduce back reflection from the end face 72.To protect the end face 72 from damage and impurities until use, the cap24 (FIG. 3) may be placed over the adjustable ferrule 22 and secured tothe connector element 20 by engaging the outer threads on the cap 24with the inner threads of the connector element 20.

After polishing or cleaving, the set screw 46 is disengaged from theadjustable ferrule 22, and the adjustable ferrule 22 is manipulated torecess the end face 72 from the proximal end of the adjustable ferrule22. In particular, the adjustable ferrule 22 is rotated to disengage orunscrew the threaded portion 54 from the threaded bore 56. This causesthe adjustable ferrule 22 to translate longitudinally in the proximaldirection with respect to the optical fiber 28, thereby recessing theend face 72 from the proximal end P of optical fiber connector 10 by adistance d. Recessing the end face 72 minimizes damage to the end face72 during use of the optical fiber 28. In some embodiments, the end face72 is recessed from the proximal end P by less than 0.5 mm. When the endface 72 has been recessed the desired distance d, the set screw 46 maythen be actuated to engage the adjustable ferrule 22 to ensure that theadjustable ferrule 22 does not move with respect to the optical fiber 28during use. In alternative embodiments, the end face 72 may bepositioned flush with the proximal end P or the end face 72 may protrudefrom the proximal end P, depending on the application of the opticalfiber connector 10.

FIG. 5A is a cross-sectional view and FIG. 5B of an embodiment of aprotective shell 100 suitable for securing around the optical fiberconnector 10. The protective shell 100 includes a cavity 101 thataccommodates the optical fiber connector 10. The protective shell 100may be used, for example, to keep the connector 10 clean and dry whenthe optical fiber connector 10 and optical fiber 28 are submerged in asolution for cleaning the optical fiber. In addition, the protectiveshell 100 may be secured around the optical fiber connector 10 duringshipping and/or storage of the optical fiber connector 10 to protect theoptical fiber connector 10 from damage and contamination.

The protective shell 100 includes a proximal portion 102 and a distalportion 104. The proximal portion 102 includes a convex proximal end 106that is disposed a distance from the adjustable ferrule 22 (FIG. 1) whenthe protective shell 100 is assembled around the optical fiber connector10. This protects the end face 72 of the fiber core 70 from and damageand debris during transport and storage, for example. The proximalportion 102 also includes a distal end 107 that is open to the cavity101. In some embodiments, the cavity 101 includes a taper 108 thatexpands toward the distal end 107 of the proximal portion 102. In someembodiments, the proximal portion 102 is comprised of an autoclavablematerial, such as polyether ether ketone (PEEK), polyetherimide (e.g.,ULTEM®), aluminum, stainless steel, or nickel-plated brass.

The distal portion 104 includes a convex distal end 110 and a proximalend 112 that includes a neck 114. The neck 114 is sized and shaped to bereceived by the open distal end 107 of the proximal portion 102 andsecured therein. In some embodiments, the neck 114 is secured withrespect to the open distal end 107 with friction (e.g., by causing theneck 114 to be urged against the taper 108). In other embodiments, theneck 114 and the cavity 101 at the distal end 107 of the proximalportion 102 include threads to threadedly secure the proximal portion102 with respect to the distal portion 104. An autoclavable sealingstructure (e.g., a high temperature o-ring) may be disposed between theproximal portion 102 and distal portion 104 to deal the interfacebetween these two structures. In some embodiments, the distal portion104 is permanently secured the distal end D of the connector 10. Inother embodiments, the distal portion 104 is removably securable to thedistal end D.

The distal portion 104 may further include a nipple 120 that extendsfrom the distal end 108. The nipple 120 may be configured to couple toan adapter 122. In some embodiments, the nipple 120 is externallythreaded to couple with an internally threaded adapter 122. In someembodiments, the adapter 122 is a Tuohy Borst type adapter. A sealingmember 124 and a metal element 126 are secured between the nipple 120and the adapter 122 when the protective shell 100 is assembled. Thesealing member 124 is compressed by the metal element 126 when theadapter 122 is secured to the nipple 120, which seals the lumen of theconnector 10 and prevents ingress of contaminants and liquids.

The adapter 122 may also include an attachment member 130 that providesan interface for securing the strain relief sleeve 26 to the distal endof the protective shell 100. In some embodiments, the strain reliefsleeve 26 is permanently affixed to the attachment member 130. Theoptical fiber 28 may be threaded through the optical fiber connector 10contained within the protective shell 100 and out of the protectiveshell 100 through the distal end of the strain relief sleeve 26.

In summary, the present disclosure relates to a connector for an opticalfiber including a housing defining a lumen and a having proximal end anddistal end, and an adjustable ferrule secured to the proximal end of thehousing and rotatable with respect to the housing to translate aproximal end of the optical fiber longitudinally with respect to aproximal end of the adjustable ferrule.

Various modifications and additions can be made to the exemplaryembodiments discussed without departing from the scope of the presentinvention. For example, while the embodiments described above refer toparticular features, the scope of this invention also includesembodiments having different combinations of features and embodimentsthat do not include all of the above described features.

I claim:
 1. A connector for an optical fiber, the connector comprising:a housing defining a lumen and including a proximal end and distal end;a collet configured to receive a portion of the optical fiber, thecollet disposed in the lumen such that the collet holds the opticalfiber in place with respect to the housing; an adjustable ferrulesecured to the proximal end of the housing and rotatable with respect tothe housing to translate a proximal end of the optical fiberlongitudinally with respect to a proximal end of the adjustable ferrule;a connector element secured to the proximal end of the housing with theadjustable ferrule, wherein the connector element is rotatable withrespect to the housing; and a collar disposed around the housing, thecollar secured to the connector element and spaced from the housing suchthat rotation of the collar rotates the connector element with respectto the housing.
 2. The connector of claim 1, wherein the connectorelement defines a threaded annular cavity, and wherein the connectorfurther comprises: a cap including an outer thread that is securable tothe threaded annular cavity to cover the adjustable ferrule.
 3. Theconnector of claim 1, wherein the housing comprises: a first couplingelement; and a second coupling element threadedly secured to the firstcoupling element.
 4. The connector of claim 3, and further comprising: ahousing set screw receivable in a radially directed threaded boreextending through the first coupling element and engageable with thesecond coupling element to lock the second coupling elementlongitudinally with respect to the first coupling element.
 5. Theconnector of claim 1, and further comprising: a ferrule set screwreceivable in a radially directed threaded bore extending through thehousing and engageable with the adjustable ferrule to lock theadjustable ferrule longitudinally with respect to the housing.
 6. Aconnector for an optical fiber, the connector comprising: a housingdefining a lumen and including a proximal end and distal end; anadjustable ferrule secured to the proximal end of the housing androtatable with respect to the housing to translate a proximal end of theoptical fiber longitudinally with respect to a proximal end of theadjustable ferrule; a connector element secured to the proximal end ofthe housing, wherein the connector element is rotatable with respect tothe housing; and a collar disposed around the housing, the collarsecured to the connector element and spaced from the housing such thatrotation of the collar rotates the connector element with respect to thehousing.
 7. The connector of claim 6, wherein the connector element issecured to the proximal end of the housing with the adjustable ferrule.8. The connector of claim 6, wherein the connector element defines athreaded annular cavity, and wherein the connector further comprises: acap including an outer thread that is securable to the threaded annularcavity to cover the adjustable ferrule.
 9. The connector of claim 6,wherein the housing comprises: a first coupling element; and a secondcoupling element threadedly secured to the first coupling element. 10.The connector of claim 9, and further comprising: a housing set screwreceivable in a radially directed threaded bore extending through thefirst coupling element and engageable with the second coupling elementto lock the second coupling element longitudinally with respect to thefirst coupling element.
 11. The connector of claim 6, and furthercomprising: a ferrule set screw receivable in a radially directedthreaded bore extending through the housing and engageable with theadjustable ferrule to lock the adjustable ferrule longitudinally withrespect to the housing.
 12. An optical fiber assembly comprising: anoptical fiber; a housing defining a lumen and including a proximal endand distal end; an adjustable ferrule secured to the proximal end of thehousing and rotatable with respect to the housing to translate aproximal end of the optical fiber longitudinally with respect to aproximal end of the adjustable ferrule; a connector element secured tothe proximal end of the housing wherein the connector element isrotatable with respect to the housing; and a collar disposed around thehousing, the collar secured to the connector element and spaced from thehousing such that rotation of the collar rotates the connector elementwith respect to the housing.
 13. The optical fiber assembly of claim 12,wherein the connector element defines a threaded annular cavity, andwherein the connector further comprises: a cap including an outer threadthat is securable to the threaded annular cavity to cover the adjustableferrule.
 14. A connector for an optical fiber, the connector comprising:a housing defining a lumen and including a proximal end and distal end;an adjustable ferrule secured to the proximal end of the housing androtatable with respect to the housing to translate a proximal end of theoptical fiber longitudinally with respect to a proximal end of theadjustable ferrule; a connector element secured to the proximal end ofthe housing wherein the connector element is rotatable with respect tothe housing, wherein the connector element defines a threaded annularcavity; and a cap including an outer thread that is securable to thethreaded annular cavity to cover the adjustable ferrule.
 15. Theconnector of claim 1, wherein the collet includes tapered ends, whereinthe lumen is sized such that the tapered ends of the collet are urgedagainst ends of lumen, and wherein the ends of the lumen are shaped suchthat the tapered ends of the collet are clamped against the opticalfiber to hold the optical fiber in place with respect to the housing.